Information courtesy of consumer guide. There are a few obvious ones missing. Where is the pump for the rear washer? mine stopped working.

Our reliability study for this generation Hummer H3 includes details on average repair costs, manufacturer recalls, and everything you need to know to gauge the long-term reliability of this generation Hummer H3 .
Trouble Spots

Consumer Guide's® Auto Editors have scoured repair bulletins and questioned mechanics to search for commonly occurring problems for a particular vehicle. In some cases we also give possible manufacturer-suggested solutions. In many instances these trouble spots are Technical Service Bulletins posted by the manufacturer, however, we have our own expert looking at additional vehicle problems.

Airbags: The airbag warning light may no go off due to a faulty seat belt tension sensor in the right front seat belt retractor assembly. (2006-07)

Check-engine light: The engine may run at lower power and the check engine light may illuminate if the engine was started with a weak battery. (2006-07)

Coolant leak: Coolant leaks from the reservoir when vehicle driven at increased angles such as off-road requiring replacement with revised component. (2006)

Electrical problem: When using a portable music player (e.g. iPod) there may be noise in the car's speakers whenever the vehicle's power adapter is used and a ground loop isolator (from Radio Shack) is required between the device and the power outlet to prevent the noise. (2006-07)

Electrical problem: The trailer wiring harness can contact the muffler and melt rendering the circuits inoperative. (2006)

Electrical problem: The DVD monitors in the front seat headrests may quit working because the video feed cable comes loose requiring installation of cable clamps. (2006-08)

None: There was a campaign to replace the jack with a more durable on for some early model year vehicles. (2006)

Tail/brake lights: The taillight housing may come loose requiring a redesigned retainer. (2006)

Water pump: There was a campaign to replace the rear window washer pump. (2006)

Consumer Guide® Estimated Repair Costs

This table lists costs of likely repairs for comparison with other vehicles. The dollar amount includes the cost of the part(s) and labor (based on $50 per hour) for the typical repair without extras or add-ons. Like the pricing information, replacement costs can vary widely depending on region. Expect charges at a new-car dealership to be slightly higher.
Item NameRepair CostA/C Compressor$510Alternator$640Automatic Transmission or Transaxle$1,950Brakes$600Constant Velocity Joints$1,325Exhaust System$375Radiator$425Shocks and/or Struts$1,105Timing Chain or Belt$650

 

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